Table 3.

Studies reporting frequency of tremor in idiopathic cervical dystonia patients.

Author/year		No of patients	Number of cervical dystonia patients	Frequency of head tremor
Huizdosova et al [8]	2020	120	Cervical dystonia	58.3 % (n = 70)
Merola et al [9]	2019	1608	Cervical dystonia	18.1% (n = 291)
Gigante et al [10]	2015	173	72 cervical dystonia patients	Overall 34% (n = 59) had tremor [12 patients- head tremor 34 patients-arm tremor 13 patients-both sites]
Pandey et al [11]	2017	90	Adult onset isolated dystonia Cervical dystonia-41 Limb dystonia-34 Cranial dystonia-15	Overall 45.5% (n = 41) Cervical dystonia-21(51.2%)
Erro et al [12]	2013	473	Adult-onset primary dystonia patients including 207 patients with cervical dystonia	Overall 55.4% (n = 262) had tremor; 196 patients (41.4%) had head tremor
Defazio et al [13]	2013	429	Primary adult onset dystonia patients including 118 cervical dystonia patients	22/34 (64.7) patients with tremor had cervical dystonia
Pal et al [14]	2000	114	Cervical dystonia	68.4% (n = 78) had head tremor and 34.6% of them (27) had tremor as one of the first symptoms
Deuschl et al [15]	1997	55	Idiopathic spasmodic torticollis	60%
Chan et al [16]	1991	266	Idiopathic cervical dystonia	28%
Jankovic et al [17]	1991	300	Cervical dystonia	71%
Couch et al [18]	1976	30	Torticollis	26 (86.6%)
Marsden et al [19]	1971	42	Idiopathic torsional dystonia	6 (14%)